Degenerative joint disease (DJD), also known as osteoarthritis or “wear and tear” arthritis occurs in middle-aged or older, large breed dogs.  It is more common in overweight dogs, those that have been heavily-exercised throughout their lives, such as working dogs, and also in those breeds prone to developmental joint problems, such as hip and elbow dysplasia. Joints are lined with cartilage and contain a small quantity of lubricating joint fluid. DJD is associated with damage and fissuring of these cartilages with the cartilage eventually thinning and being lost. The development of DJD is associated with lameness, pain and swelling of the joint and restriction of joint movement Eventually loss of muscle mass in the affected limbs may impair mobility and cause the animal to go off their legs. Diagnosis is usually made by taking x-rays of the affected joint(s) but, on rare occasions, joint fluid may need to be sampled or the joint may need to be biopsied to rule out other causes of disease.

Once a joint has developed DJD, it cannot be cured. The goal of treatment is to decrease pain, minimise lameness, improve mobility, maintain muscle bulk and provide a good quality of life for affected patients. There are a few simple steps that can greatly improve joint function.

WEIGHT REDUCTION

Most dogs with DJD are overweight or obese. Strenuous efforts should be made to reduce the dog’s bodyweight to the normal lean body weight for the breed. For example a <placew:ston>Labrador affected by DJD should be dieted to a bodyweight of 29-33 Kg. Weight cannot be lost by increasing exercise as this would cause increased lameness and joint pain. If your dog is more than a few pounds overweight, weight reduction is best achieved by feeding proprietary low calorie diets. Our nursing staff can assist with dietary advice, weighing your dog and can provide many tips on how best to achieve controlled weight reduction. Aim for a weight loss of 1-1.25% of bodyweight per week. If your pet is severely overweight it may take 5 months for them to achieve normal lean bodyweight.

EXERCISE RESTRICTION

Pets with DJD will often go lame after high impact exercise. High impact exercise includes running off the lead, playing with other dogs or playing ball games. Low impact exercise includes walking on the lead and swimming. Enough exercise should be given each day to ensure your pet’s mental health but the quantity of high impact exercise should be strictly restricted. If your pet goes lame after exercise, high impact exercise should be reduced until the joints become less painful. Ball games are best avoided in dogs with joint disease. Regular, gentle exercise is thought to improve cartilage nutrition and to maintain muscle bulk. If your pet is unable to exercise at all, gentle walking on a soft surface, such as a sandy beach, may be beneficial. It helps to walk such animals very slowly with “old man” steps for, if they are made to hurry, they will often carry the affected limb or refuse to go further.

Non-weight bearing exercise is excellent exercise for joints with DJD. There are several hydrotherapy units now available for dogs in this area. However, few are backed by the assistance of a trained veterinary physiotherapist. Canine physical rehabilitation is best undertaken in an appropriate program of exercise under the guidance of a physiotherapist. The best facilities use water-walking  and jet-swimming tanks to accurately control exercise levels.

JOINT SUPPLEMENTS

Joint supplements are widely recommended to treat DJD in both pets and humans. However, there is, as yet, a lack of good evidence of sustained long-term benefit associated with the use of joint supplements. Joint supplements are very safe, are thought to encourage cartilage repair and are widely used throughout the veterinary profession.

Chondroitin/Glucosamine supplements. These substances are the “building blocks” of cartilage. Dogs do not absorb glucosamine in the same manner as humans and so doggy specific (D-glucosamine) supplements are required. We recommend the use of “Seraquin”, a palatable tablet that is easy to administer. This is given at a high dose for 6 weeks and is then the dose is reduced to half for maintenance.

Fatty acid supplementation has been shown to have significant anti-inflammatory effects in both humans and dogs. Omega 3 (marine fish) oils may work best when combined with  omega 6 fatty acids (such as evening primrose oil). We recommend a daily 1000mg capsule of evening primrose oil with a supplement of cod liver oil twice weekly. Note- dogs have a diet that is very high in vitamin A, thus cod liver oil supplementation should not be overdone. The smallest human capsule twice weekly is adequate.

CARTROPHEN INJECTIONS (Pentosan Polysulphate)

This substance is given once weekly for 4 weeks by injection. It binds to damaged cartilage and promotes healing, as well and inhibiting damaging enzymes within inflamed joints. The beneficial effects may last for 6-8 months after the course of injections. A new course of injections can be given at this time. Alternatively, the dog can be maintained on single injections every two months after the primary course. Cartrophen does thin the blood and any pain-killing drugs should be stopped for 24 hours before and after injection. Occasionally, we may inject drugs such as cartrophen, directly into the joint under anaesthesia.

NON-STEROIDAL ANTI-INFLAMMATORY DRUGS (NSAIDS)

All patients with DJD may need anti-inflammatory and pain-killing drugs from time to time. Human preparations should never be used as some, such as ibuprofen, are highly toxic to dogs. We use a range of modern, “cartilage-friendly” drugs that have very few side-effects. This means that they are safe in the older patient and can be used continuously, if required.  We recommend meloxicam (Metacam) for routine use as it is easy to administer, accumulates in inflamed tissues (and thus may work better after it has been used for some time) and is very safe indeed. The manufacturers of Metacam currently provide a support program (Metacam Continuous Care) for the owners of dogs being continually treated with Metacam – please ask any member of staff for details.  The modern NSAIDS are thought to broadly the same potency but some drugs may suit some dogs better than others. If Metacam does not seem effective, other drugs can be tried. If NSAIDs are administered long-term it is best to check kidney function by way of a blood test every six months. In cases of very severe pain, additional pain-relief can be offered in the form of codeine tablets or opiate skin patches.

JOINT REPLACEMENT

If your pet has very severe joint problems, joint replacement is now undertaken at several specialist centres. Hip replacements in large breed dogs, using human hip implants,  have been performed in veterinary medicine for many years and give very good results. More recently smaller implants for small-breed dogs have become available. Elbow replacements are also now being pioneered at specialist centres such as the <placew:ston><placenamew:ston>Queen Mother <placetypew:ston>Hospital, Hertfordshire.